Steele, the state's lieutenant governor, framed several issues ? jobs, energy, health insurance ? in terms of how businesses are affected.
Cardin painted Steele as a President Bush crony.
Steele criticized the ways of "old Washington."
The event capped a week in which the Hagerstown-Washington County Chamber of Commerce hosted three campaign events.
On Tuesday, Democratic gubernatorial candidate Martin O'Malley, the mayor of Baltimore, addressed a chamber lunch. Two days later, the chamber had a forum with the 10 candidates for Washington County Commissioner.
Friday's Senate lunch brought Cardin and Steele together for one of the few times this campaign season, plus a media pack from Baltimore and Washington, D.C.
Cardin sounded off several times on the deficit, calling it "the most dangerous" debt the country has had.
He also spoke in favor of health insurance for everyone in the country and "an Apollo-type project" to wean the U.S. from foreign-oil dependence, a reference to America's effort to reach the moon.
Steele said he wants business people ? the entire state, really ? to have "a seat at the table" when issues are discussed. He said those in power haven't solved immigration, energy, health-care and Social Security problems.
Moderator Suzanne Hayes touched on several of those points in the audience questions she read.
Neither candidate had a specific plan for the most locally centered question: how to get Washington County more money to improve interstates 81 and 70 and build a southern bypass.
Cardin said he'd work with county leaders, adding that he opposes tolls on Interstate 81.
Steele said the state needs a transportation policy. "Some folks think that there aren't roads out here," he said, drawing laughs.
The two candidates noticeably differed on the federal gasoline tax, which Steele wants to suspend and Cardin does not.
Both spoke about the Iraq war, but in different realms.
Cardin said his opposition of the war four years ago was unpopular in Maryland, but he based it on evidence that Iraq was not connected to the Sept. 11, 2001, terrorist attacks and didn't have nuclear weapons.
Steele focused on America's duty to stay in Iraq for now. He said pulling troops out right away or announcing a timetable for withdrawal would be "bad policy."
"What's in place after the last soldier leaves?" he asked.
Cardin called the federal No Child Left Behind Act, which sets school accountability standards, an unfunded mandate. Steele countered that he has seen and heard what schools across the state need and asked, "Mr. Cardin, when was the last time you were in a third-grade classroom?"
In response to a question from Hayes, Cardin said he is pro-choice on abortion, believes in the Constitutional right to own guns and doesn't support gay marriage.
Steele was not asked for his position on those issues.
Some of the most animated talk was about a Democratic operative fraudulently accessing Steele's credit report. A woman with the Democratic Senatorial Campaign Committee has pleaded guilty in the incident.
Cardin said Steele should stop alleging that his campaign was connected to the crime, but Steele said Cardin is part of a Democratic structure that's responsible and hasn't apologized.
Winners of their respective Sept. 12 primaries, Cardin and Steele are competing for the U.S. Senate seat Democrat Paul S. Sarbanes has held since 1977. Sarbanes isn't running for re-election.
Kevin Zeese, who has the backing of the Green, Libertarian and Populist parties, also will be on the ballot for the Nov. 7 general election.